Blower for vehicle-drying installation

ABSTRACT

A blower, designed particularly for use in the air drying of vehicular surfaces in car-washing stations, has a cylindrical housing formed at one end with an outlet slot for the discharge of an air stream generated by a fan mounted within the housing near the other end thereof. A liner of soundproofing material, such as foam plastic, extends from the vicinity of the fan toward the discharge end and defines a progressively narrowing air channel terminating at the outlet slot.

United States Patent 1191 Burger 1 1 Jam 29, 1974 [54] BLOWER FQR VEHICLE-DRYING 2,126,581 8/1938 Samuels .1 219/370 I S ON 3,263,341 8/1966 Allen 1 34/229 1,970,674 8/1934 Siebert et a1... 1. 34/229 [75] Inventor: Horst g Neusass, Germany 2,330,701 9/1943 Gerber...., 415/119 x [-73] Assigneel Bowl Bohler & Weber 2,758,392 8/1956 Vam et a1. ..34/243 X s n n a gs u g, FOREIGN PATENTS 0R APPLICATIONS Germany 563,990 1/1958 Belgium .j. 15/1310. 2 22] Filed; 27 971 746,702 3/1956 Great Britain 415/119 [21] Appl. No.: 219,592 [30] Foreign Application Priority: D515 7 A '7 P r imary Examiner-J91! J. y'

- Assistant Examiner-James C. Yeung Aug. 30, 1969 Germany 1780316 Attorney, Agent, or FirmKarl F. Ross Oct. 14,1969 Germany ..l809905 Related US. Application Data [63] Continuation ,of Ser. No. 854,431, Sept. 2, 1969, [57] ABSTRACT abandoned [52] CL 34/229 34/222 A blower, designed particularly for use in the air dry [51 1 Int. Cl. M 6 19/00 ing of vehicular surfaces in car-washing stations, has a ['58] Field 25/314 cylindrical housing formed at one end with an outlet 1S/DIG 405 239/592 slot for the discharge of an air stream generated by a 219/369 3 fan mounted within the housing near the other end thereof. A liner of soundproofing material, such as [56] References Cited foam plastic, extends from the vicinity of the fan toward the discharge end and defines a progressively UNITED STATES PATENTS narrowing air channel terminating at the outlet slot. 2,415,621 2/1947 Arnhym 219/369 x 2,478,559. 8/1949 Bergeron 7 Claims, 5 Drawing Figures 2,502,947 4/1950 Hess 431/158 X PATENTEDJAH 29 I974 SHEET 1 [IF 2 PATENTEBJAN 29 m4 3 787' 986 SHEET 2 0F 2 I I FIG. 5

BLOWER FOR VEHICLE-DRYING INSTALLATION I of the frame in such a way that the airstream issuing from each blower nozzle be spread into a broad, thin sheet sweeping a substantial portion of the surface to be dried.

In a conventional blower with a generally cylindrical housing, in which the air is axially circulated by one or more fans having blades rotating in a traverse plane, the generation of anairstream substantially wider than the sweep diameter of the fan blades has heretofore required the provision of a plenum chamber into which the high-velocity air flow is directed to build up a substantially uniform pressure behind an elongate nozzle at the discharge end of the housing. The interposition of such a plenum chamber entails a considerable loss of energy and, therefore, a substantial lowering of the efficiency of the blower. If the plenum chamber is omitted, however, the discharge velocity decreases sharply from the center of the nozzle toward its end and may even be locally inverted, the result being a high degree of tubulence in lieu of the desired laminar flow.

The general object of my present invention, therefore, is to provide an improved air blower for the purpose set forth, and for related purposes, in which the aforestated drawbacks are avoided.

Another object is to provide means for minimizing the objectional noise generated by conventional air blowers.

These objects are realized, pursuant to my present invention, by the provision of a blower of the aforedescribed axial type wherein, however, the discharge end of the generally cylindrical housing has an outlet slot which, while extending over a major part of the housing diameter in an axial plane, has a length not greater than the sweep radius of the fan blades by which air is aspirated into the housing through the opposite, preferably screened intake end. A lining, which may be unitary or split into several portions, extends within the housing from the region of the fan blades to the discharge end and forms an air channel whichterminates at the outlet slot and narrows progressively, in an axial plane perpendicular to that of the slot, to a width substantially equaling the slot width. This width, accordingly, is a small fraction of the sweep diameter of the fan blades whereby the air flow generated by these blades is gradually compressed into a considerably smaller crosssectional area with consequent acceleration of the flow over the entire length of the slot. As the air leaves the nozzle formed by the slot and the adjoining lining surface, the lines of flow tend to spread out laterally to produce a divergent sheet of air which, when trained from above onto a vehicle passing underneath, sweeps a large portion of the vehicular surface.

In accordance with another feature of my invention, the noise normally encountered with blowers of this general type is minimized by making the lining of formable body.

For a smoother transition of the airstream from the interior of the nozzle to the open atomsphere, the lining may be slightly flared outwardly at the slot so as to present a rounded lip, particularly along the major edges of the slot periphery.

The invention will be described hereinafter in greater detail with reference to the accompanying drawing in which:

FIG. 1 is an isometric view of a blower embodying my invention;

FIG. 2 is an axial sectional view of the blower shown in FIG. 1;

FlG. 3 is a front-elevational view of a vehicular drying station equipped with several blowers of the type shown in FIGS. 1 and 2;

FIG. 4 is a side-elevational view of the drying station shown in FIG. 3; and

FIG. 5 is a perspective view. of a drying tunnel equipped with several blowers similar to that shown in FIGS. 1 and 2.

The air blower 1 shown in FIG. 1 and 2 comprises a cylindrical housing 2, e.g. of sheet metal, wherein a fan motor 3 with a rotatable hub 3' is axially supported with the aid of several radial stays 6 of suitably streamlined profile acting as stationary guide vanes. Hub 3' supports a set of propeller blades 4 which aspirate the outside air through a protective screen 5 at the rear end of housing 2. I

A liner 9 of expanded, open-celled polymeric material (e.g. polystyrene), extending from the vicinity of fan 3, 4 to the front end of housing 2, defines a progressively converging channel 8 which terminates at an elongate slot 10 lying in the median horizontal plane of the housing as viewed in FIGS. 1 and 2). The length of slot 10 is a little less than the housing diameter and is therefore slightly exceeded by the sweep diameter of the fan blades 4. The width of slot 10, on the other hand, is a minor fraction of the housing diameter and substantially corresponds to the width of channel 8 at its narrowest point. A slotted shield 10 with an elongate aperture 17 of elliptical shape, which may be integral with housing 2, holds the liner 9 in position; the inner edge of the shield-aperture 17 is partly overlain by the The constriction of the air channel 8 downstream of fan 3, 4 eliminates minor vortices which tend to develop in the dead space just behind the fan motor 3, as illustrated in FIG. 2.

As shown in FIG. 1, the housing 2 of blower 1 may be provided with a pivoted bail 12 by which the blower can be suspended, e.g. with the aid of an eye 13, from a suitable support.

FIGS. 3 and 4 show three blowers 1, each of the type described in connection with FIGS. 1 and 2, suspended from the lintel a of a portal frame 15 forming part of a car-drying installation. The blowers l, suspended at the center and at the ends of the lintel with the aid of bails 12 a and in the case of the two lateral blowers) stays l2b,are trained upon an automotive vehicle 14 relatively to which the frame 15 is slowly displaced on rollers 16 guided in channels 18. The jams 15b of frame 15 are shown to be of the telescopic extensible type to allow the height of the frame to be varied in accordance with the dimensions of the vehicle to be dried. The stays 12b may be adjustable to alter the inclination of the lateral blowers. I

In FIG. 5 l have shown a drying tunnel 25, which also may form part of a vehicle-washing station, having several blowers 1A, 1B suspended therein for manual handling during the drying operation. Blower 1A is shown mounted, by way of a tension spring 19, from an overhead rail 21 with the aid of a slider 26 movable along this rail. Blower 1B is suspended from a sidewall of the tunnel by way of a swingable arm 20. The spring 19 of blower 1A has been replaced in the case of blower 18 by a balanced pulley-type suspension 22, as conventionally used in drop lamps and the like, enabling the stabilization of this blower at any desired level. Both blowers 1A and 1B are provided with pistol grips 23 by which they can be manually moved across any part of the vehicle or other structure to be swept by their airstreams. The partial or complete balancing of the weight of these blowers by the suspension means 19, simplifies the task of the operator in moving these devices about.

A pushbutton-type trigger 24 on each handle 23 serves for the starting and stopping of the fan motor of the blower which is energized through a wire separate from or forming part of the corresponding suspension cable 27A, 27B.

In the case of a light-weight blower, the device could be designed completely as a bnad-carried tool without weight-compensating suspension.

The relatively short axial length of the discharge channel 8 of my improved blower minimizes frictional losses and insures a high delivery speed at the output nozzle 10. Compared with conventional blowers of like capacity, using a plenum chamber, the expenditure of energy is reduced by up to 75 percent.

I claim:

1. A vehicle-drying installation, comprising a structure straddling the path of a vehicle to be dried; an air blower on said structure including a generally cylindrical housing of rigid sheet material having an open in take end and a discharge end trasverse to the housing axis, the latter end being trained upon said path and having an outlet slot extending over a major part of the housing diameter on opposite sides of a first axial plane; fan means disposed in said housing adjacent said intake end for generating an axial air flow, said fan means being provided with blade means rotatable in a transverse plane with a sweep radius at least equal to the length of said slot; and a liner of sound-absorbing open-celled polymeric material fitted into said housing and increasing progressively in thickness from the region of said fan means to the vicinity of said discharge end, said liner: forming the sole boundary of an air channel which extends from the region of said fan means to thevicinity of said discharge end and terminates at said outlet slot, said air channel narrowing progressively in a second axial plane perpendicular to said first axial plane to a width substantially equaling that of said slot. 7

2. An installation as defined in claim 1 wherein said housing is provided at said discharge end with a shield having an elongate aperture of generally elliptical shape substantially coextensive with said slot, said liner bearing upon said shield and having a flared portion protruding outwardly through said aperture along the major edges of said slot.

3. An installation as defined in claim 1, further comprising handle means on said housing and switch means on said handle means for controlling said fan means.

4. An installation as defined in claim 1 wherein said structure includes suspension means for said blower provided with balancing means for at least partly compensating the weight of ,said blower while allowing a substantially unhindered lateral displacement thereof.

5. An installation as defined in claim 4 wherein said structure comprises a movable frame with a lintel, said suspension means securing said blower to said lintel.

6. An installation as defined in claim 5 wherein said frame is provided with extensible jambs.

7. An installation as defined in claim 1 wherein said fan means includes a motor with a streamlined body centered on said axis and radially extending stays of streamlined profile supporting said streamlined body on said housing.

# t t i 

1. A vehicle-drying installation, comprising a structure straddling the path of a vehicle to be dried; an air blower on said structure including a generally cylindrical housing of rigid sheet material having an open intake end and a discharge end trasverse to the housing axis, the latter end being trained upon said path and having an outlet slot extending over a major part of the housing diameter on opposite sides of a first axial plane; fan means disposed in said housing adjacent said intake end for generating an axial air flow, said fan means being provided with blade means rotatable in a transverse plane with a sweep radius at least equal to the length of said slot; and a liner of soundabsorbing open-celled polymeric material fitted into said housing and increasing progressively in thickness from the region of said fan means to the vicinity of said discharge end, said liner forming the sole boundary of an air channel which extends from the region of said fan means to the vicinity of said discharge end and terminates at said outlet slot, said air channel narrowing progressively in a second axial plane perpendicular to said first axial plane to a width substantially equaling that of said slot.
 2. An installation as defined in claim 1 wherein said housing is provided at said discharge end with a shield having an elongate aperture of generally elliptical shape substantially coextensive with said slot, said liner bearing upon said shield and having a flared portion protruding outwardly through said aperture along the major edges of said slot.
 3. An installation aS defined in claim 1, further comprising handle means on said housing and switch means on said handle means for controlling said fan means.
 4. An installation as defined in claim 1 wherein said structure includes suspension means for said blower provided with balancing means for at least partly compensating the weight of said blower while allowing a substantially unhindered lateral displacement thereof.
 5. An installation as defined in claim 4 wherein said structure comprises a movable frame with a lintel, said suspension means securing said blower to said lintel.
 6. An installation as defined in claim 5 wherein said frame is provided with extensible jambs.
 7. An installation as defined in claim 1 wherein said fan means includes a motor with a streamlined body centered on said axis and radially extending stays of streamlined profile supporting said streamlined body on said housing. 